Headlight



Feb. 24, 1931. H, WOOD' 1,793,662

HEADLIGHT Filed June '7 92 William 15'. Wood Z v Inventor j W M A. ztoz-neys 6 filament bulb, two beam patterns similar in necessary thatthe intensity Patented Feb. 24, 1931 WILLIAM H. WOOD, OF

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scorn EUCLID, OHIO HEADLIGHT Applicationnled June 7, 1926. Serial No.114,167.

This invention relates to vehicle headlights and has for its object toprovide in a cheap, simple, and convenient manner, a reflector whichshall produce,'when used With atwo all respects save in elevation andwithout? need for any difi'using, diverging, or correcting lenses. Itisat leastdesirable if not of the light vary at different partsofthebeam, the region of greatest intensity being symmetrical about thevertical axis and approximately at the top of each beam. By doublefilament lamp I mean a lamp bulb having two light sources so arranged asto be usable selectively to produce an elevation or depression of thebeam.

It has heretofore been suggested to modify a paraboloid reflector by atransversefiattening of numerous narrow vertical Zones thereof, butowin' to certain peculiarities of optics such a rel? ctor, while itworks very satisfactorily with a single filament bulb, is whollyunsatisfactory when used with a bulb having two independently usablefilaments'located one above the other. The result in such case isprimarily a wide anddisordered diffusion with no substantial control ofthe beam.

According to my invention the two lateral portions of the reflector aremade substantially paraboloid with their axis horizontal or nearly soand the lamp bulb located-with its two filaments one above the other andsubstantially in the same vertical line with the focal point thereof.The remainder of the reflector is striated vertically as heretoforedescribed except that in addition to the striations the surfaces, bothabove and below the axis, are leaned downwardly below the surface ofrevolution defined by said lateral portions.

In the accompanying drawings I have shown the essential elements-of myinvention Fig. 1 is a vertical sectional view through a headlightcontaining my improvements; Fig. 2 is a front elevation of the partsshown in Fig. 1; Figs. 3, 4 and 5 are front elevations of modifications;and Figs. 6 and 7 are horizontal sections on'the line 66 and 77,respectively. of Figs. 1 and 2.

small as shown in The reflector consistsof a single piece of sheet metaldrawn in dies to the desired form. The side portions 1, 1 are paraboloidsegments about the axis a.a with focal point aii .The top portion 2 andbottom portion 3 are leaned downwardly as indicated by the fact thatthey fall below the dotted lines A A of Fig. 1 which dotted line is anextension of such lateral portions 2 and 3 maybe of any ture in avertical plane but are divided into plural vertical zones each having amodified lateral curvature which I here call striations. It will'be seenthat all the striated or zoned portions are downwardly leaned ascompared with the. paraboloid portions. Generally each vertical sectionthrough the portions 2, 3, approximates moreor less closely to one ormore parabolas, generally having their axis or axes inclined asindicated at b b, and is here shown as having a focal region f 10-"cated at a lower level than the focal oint, 7.

With either filament the effect 0 the portions 1, 1 is to produce aconcentrated beam, the t w o differing only ince levation; theinclination of the ortions 2, 3 relative there,- to causes the difl dsedrays to fall chiefly be low the level '0 stance. g

The dimensions of the portions 1, 1 as compared with the portions 2, 3,are subject to wide variation;-they may be comparatively Fig. 3 or theportions 2, 3, may be small as shown in Fig. 4. I prefer to employ therelation substantially shown in Fig. 2. The axis or axes of the portions2 and 3 fall within the same vertical plane which contains the axisofthe portions 11 and the heel portion of the reflector, namely theportions falling to the rear in general of the focal plane, may consistprimarily of an extension of the portions 11 as shown in Fig. 4, or ofthe portions 2 and 3 as shown in Figs. 2, 3, and 5. In Fig. 5 I haveshown the lateral portions as formed with very shallow circumferentialstriations 1*1 in order to produce an increased degree of diffusionwithin the concentrated beam.

The striations of the upper and lower regions coupled with the downwardleaning paraboloidsegmentas. The

eslre curvathe intense beam in each inthereof as compared with the sidewings produces a reflector having a very wide focusing tolerance. Thisdevice can bemade very simply b first producing a punch turned in itsdifferent quadrants to the axes aa,

b?), after which the indicated-portions are ound or milled, either to agreater or less egree of curvature, this milling being .con-

fined only to-those parts which were turned to the axis b-b.

Having thus described my invention what Iclaim is:

1. Aheadlight reflector having a pair of opposed lateral portionslocated at and upon both sides of the horizontal axial plane and forwardof the focal plane consisting of paraboloid segments to a commonhorizontal axis,incombination with upper and lower portions located atand upon both sides of the vertical axial plane and forwardofthe focalplane leaned downwardly as compared with the paraboloid surface definedby said lateral segments, said upper and lower portions having narrowupright zones thereof flatted transversely.

2. A headlight reflector having a pair of opposed lateral portionslocated at and upon both sides of the horizontal axial plane and forwardof the focal plane defined by'the o ation of a parabola about a singlehorizont a l 'axis, in combination with upper and lower portions locatedat and near the vertical axial lane and forwardly of the focal planedeed by a surface of revolution whose vertical axial section isparabolic with its axis downwardly inclined as compared with said firstnamed axis, certain of said portions being extended to the rear of thefocal plane and defining the heel part of the reflector, and at least apart of said reflector having striated portions of modified transversecurvature to spread the light laterally.

,3. A headlight reflector having portions consisting of narrow uprightzones of're duced lateral curvature and paraboloid segments, saidsegmentsbeing located at oppo site sides of said reflector and in frontof the focal plane and having a single horizontal axis, said zonedportions including the rest of the reflector and defined by a parabolicsurface the axis of which is inclined downwardly as compared with saidfirst axi 4. The combination with a lamp bulb having two independentlyusable concentrated filaments located one above the other, of areflector having concentrating portions and diffusing portions, saidconcentrating portions defined by paraboloid segments located one ateach side of said lamp with their common axis substantially horizontal,and said diffusing portions having upright zones of reduced transversecurvature, located above and below the lamp bulb, the vertical axialsection of said reflector having a focal point on the same vertical line.with both filaments and the axis of such vertical axial section lyingin the same plane with the common axis of said paraboloid segments andinclined obliquely thereto.

5. The combination witha lamp bulb having two independently usableconcentrated filaments located one above the other, of a I 6. Areflector'having at opposite sides a pair of opposed paraboloid segmentsdefined substantially by'surfaces of revolution about a horizontal axisand the remainder of the reflector consisting of portions whose verticalsections consist essentially or parabolas whose axes lie in the samevertical plane with said first axis and are inclined forwardlyanddownwardly relative thereto and whose focal points are located on thesame vertical line with the focal point of said first segments and whosehorizontal section exhibits a series of flattened zones.

7 A reflector having two opposed lateral portions located at and uponboth sides of the horizontal axial plane and in front of the focal planedefined by the rotation of a parabola about a single horizontal axis, incombination with upper and lower portions located at and upon both sidesof the vertical' axial. section and'in front of the focal plane definedby a surface of revolution whose vertical axial section is parabolicwith its axis downwardly inclined relative to said first axis, the focalpoints of said parabolas being located in the same vertical plane,certain of said portions being extended to the rear of the focal laneand constituting the heel part of the reflcctor, portions abovementioned having striated regions of modified transverse curvature tospread the light laterally. I i

In testimony whereof I hereunto aflix my signature.-

I WILLIAM Wotan.

e horizontal axial section, and ly-- ing in the same vertical planetherewith.

and at least upper and lowerv

